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    <title>Document</title>
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<body>
    <script>
        // 输出顺序
        function fn1() {
            console.log(111);//1
            fn2()
            console.log("fn1");//4
        }
        fn1();
        function fn2() {
            console.log(22);//2
            console.log("fn2");//3
        }
    </script>
</body>

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